Why is my garbage disposal leaking from the bottom?

A leak from the bottom of the garbage disposal — near the reset button — means the internal seal has failed. Garbage disposals have internal seals that separate the motor from the grinding chamber. These seals are not serviceable or replaceable on most units. Once water is coming out the bottom reset area, the unit is at end of life. Replacement is the correct fix, not repair.

How do I fix a garbage disposal that leaks from the top at the sink?

A top leak (water coming from where the disposal meets the sink drain flange) is caused by a loose mounting ring or dried-out plumber's putty. To fix: turn off power at the breaker. Place a bucket under the disposal. Unmount the disposal by rotating it counterclockwise off the mounting ring. Check the putty around the sink flange. If the putty is cracked or missing, remove the flange, clean the old putty off, apply fresh plumber's putty around the underside of the flange, reseat it in the sink, and retighten the mounting assembly from below. Remount the disposal and test.

What does it mean when a garbage disposal leaks from the side?

A side leak — water dripping from the side of the disposal body — is almost always the discharge gasket between the disposal and the drain pipe. The discharge outlet has a rubber gasket and is held by two bolts. Tighten those bolts first. If tightening doesn't stop the leak, the gasket is damaged and needs replacement. Remove the bolts, pull the drain pipe away, replace the gasket, and reassemble.

Can I fix a garbage disposal leak myself without a plumber?

Yes, for top and side leaks. A top leak (sink flange) requires re-seating the flange with plumber's putty — a one-to-two hour job with basic tools. A side leak (discharge gasket) is a simple gasket swap that takes under an hour. A bottom leak is different: it means the motor seals have failed and the unit needs replacement, which is also a DIY-friendly job but requires buying a new disposal.

Should I repair a leaking garbage disposal or replace it?

Repair if the leak is at the sink flange or side discharge — these are inexpensive fixes. Replace if the leak is from the bottom (internal seal failure), if the unit is more than 10 years old, if it jams frequently, or if it grinds poorly. A new mid-range disposal costs $120–$200 and installs in under an hour. Paying a plumber to repair an aging disposal rarely makes sense economically.

How do I tighten a garbage disposal sink flange?

The sink flange is held against the sink basin by a mounting assembly underneath — three mounting screws on the lower mounting ring press a snap ring against the flange body. To tighten: unmount the disposal, look at the underside of the sink flange. The mounting assembly has three screws equally spaced around the ring. Tighten each screw evenly with a screwdriver until the flange is snug against the sink. Do not overtighten — the goal is firm contact with even pressure. If the flange still moves after tightening, the plumber's putty seal is compromised and needs to be replaced.

How to Fix a Leaking Garbage Disposal: Sink Flange, Side Leak, and Bottom Drain

Where the leak comes from tells you exactly what failed.

Where the leak comes from tells you exactly what failed. Diagnose the location before buying any parts.

What you need

Diagnose the leak location

Before touching anything, dry the disposal and surrounding pipes with a towel. Run water and watch closely. Leak location determines the repair:

Water dripping at the sink rim or between the sink and the disposal top: sink flange leak
Water dripping from the side of the disposal body where the drain pipe connects: discharge gasket leak
Water dripping from the bottom of the unit near the reset button: internal seal failure

Confirming which location is leaking saves time. A disposal can have more than one source — fix the obvious one and recheck.

Fix a top leak: tighten or reset the sink flange

Turn off power at the circuit breaker. Place a bucket under the disposal. Unmount the disposal by inserting the wrench into the mounting lugs and rotating counterclockwise — the unit drops free.

Look at the underside of the sink flange. There are three mounting screws on the lower mounting ring. Tighten each screw evenly. Remount the disposal, run water, and check.

If tightening doesn’t stop the leak: the plumber’s putty under the flange has dried out and cracked. Remove the entire flange assembly by loosening the three mounting screws until the snap ring releases. Push the flange up through the sink from below and pull it out from above.

Scrape off all old putty from the sink surface and the flange. Roll fresh plumber’s putty into a rope and press it around the underside rim of the flange. Press the flange into the drain opening from above. From below, reinstall the mounting assembly — slide the gasket, backup flange, and mounting ring onto the flange neck, then press the snap ring into the groove. Tighten the three mounting screws evenly until the flange seats firmly. Scrape excess putty from above. Remount the disposal and test.

Fix a side leak: replace the discharge gasket

The discharge outlet is on the side of the disposal body — a short stub where the drain pipe connects. It is held by two bolts. Loosen both bolts and pull the drain pipe away from the outlet.

Inside the outlet opening: a rubber gasket seats against the pipe flange. If this gasket is cracked, compressed flat, or out of position, it won’t seal. Remove the old gasket.

Take the gasket to the hardware store to match it, or check your disposal model for the correct replacement part number. Most InSinkErator and Moen disposals use a universal drain gasket.

Press the new gasket into the outlet recess. Reconnect the drain pipe and tighten the two bolts evenly. Run water and check for drips.

Fix a bottom leak: replace the unit

A bottom leak means the internal motor seal has failed. Water from the grinding chamber is getting past the seal into the motor housing and dripping out the bottom drain port. This seal is not replaceable in the field.

If the disposal is under warranty, contact the manufacturer. Otherwise, replacement is the right move. A garbage disposal replacement is a direct DIY job — the mounting system is standardized. InSinkErator uses the same mounting collar across most models. A new disposal drops onto the existing mounting ring.

Turn off power at the breaker. Disconnect the drain pipe. Unmount the disposal. Disconnect the wiring. Connect the new unit to the existing wiring, mount it on the collar, reconnect the drain, and restore power.

When to replace vs repair

Repair (flange or gasket) if:

The unit grinds well and runs without jamming
It is less than 8–10 years old
The leak is confined to one external location

Replace if:

The leak is from the bottom
The unit jams repeatedly or hums without grinding
It is more than 10 years old and has multiple issues

A new mid-range disposal (1/2 to 3/4 HP) runs $120–$200 and installs in under an hour using the existing mounting hardware.

⏰ PT1H30M 💰 $10–$200

Diagnose the leak location
Dry the disposal and surrounding pipes with a towel. Run water and watch closely. Water at the sink rim or between the sink and disposal top = sink flange leak. Water dripping from the side of the disposal where the drain pipe connects = discharge gasket leak. Water dripping from the bottom near the reset button = internal seal failure. A disposal can have more than one source — fix the most obvious one and recheck.
Fix a top leak at the sink flange
Turn off power at the breaker. Unmount the disposal by inserting a wrench into the mounting lugs and rotating counterclockwise. Look at the underside of the sink flange: tighten the three mounting screws evenly. Remount and test. If still leaking: remove the flange completely by loosening the mounting screws until the snap ring releases. Scrape off all old putty. Roll fresh plumber's putty into a rope and press around the underside rim. Reinstall flange from above, tighten the three screws evenly from below, scrape off excess putty, remount the disposal.
Fix a side leak at the discharge outlet
The discharge outlet on the side of the disposal body connects to the P-trap via two bolts and a rubber gasket. Loosen both bolts and pull the drain pipe away. Inspect the rubber gasket inside the outlet opening — replace it if cracked, compressed flat, or out of position. Take the old gasket to the hardware store to match, or find the replacement by disposal model number. Press the new gasket into the outlet recess, reconnect the drain pipe, and tighten both bolts evenly. Run water and check for drips.
Bottom leak — replace the disposal
A bottom leak from near the reset button means the internal motor seal has failed — this is not field-repairable. If the disposal is under warranty, contact the manufacturer. Otherwise, replace the unit. A new disposal drops onto the existing mounting collar (most InSinkErator models use the same ring). Turn off power, disconnect the drain pipe, unmount and rewire the new disposal, reconnect the drain, restore power. Mid-range disposals cost $120–$200 and install in under an hour.

How to Fix a Leaking Garbage Disposal: Sink Flange, Side Leak, and Bottom Drain

What you need

Diagnose the leak location

Fix a top leak: tighten or reset the sink flange

Fix a side leak: replace the discharge gasket

Fix a bottom leak: replace the unit

When to replace vs repair

Free: 10-Point Home Maintenance Checklist

Save this for next time.

How to Fix a Leaking Garbage Disposal: Sink Flange, Side Leak, and Bottom Drain

What you need

Diagnose the leak location

Fix a top leak: tighten or reset the sink flange

Fix a side leak: replace the discharge gasket

Fix a bottom leak: replace the unit

When to replace vs repair

Related guides

Free: 10-Point Home Maintenance Checklist

Save this for next time.